Looks Like Immune Responses are Enduring After All
For some time, public health officials have fretted about whether immunity to COVID-19, acquired via infection or vaccination would stick. Studies showed rapid declines in antibodies during recovery from infection and thereafter.
It turns out that this concern was overblown. A study just released says bone marrow plasma cells are a persistent source of protective antibodies, and that "circulating resting memory B cells directed against the S protein were detected in the convalescent individuals." Another study, yet to be reviewed, suggests that vaccines boost this effect. In fact, some are suggesting this situation this could actually mean lifetime immunity.
Whether the same thing happens with vaccination is not clear. Most estimates suggest that vaccine immunity will last about a year. More pessimistic estimates putting the protection period at six months.
The possible shorter time frame, plus the appearance of the new variants, have the vaccine makers working on booster shots. Those are expected to be available in the fall.
It's worth noting that experts had same worries about limited immunity from infection until the above studies came along. To my knowledge, though, nobody has done bone marrow studies on vaccinated people. Maybe if they do and we are lucky, the vaccine will offer long term protection too.
Image by Bruno /Germany from Pixabay